1. Field of the Invention
This invention relates to a device for controlling the power supply to an electrical circuit such as the exposure control circuit of a camera.
2. Description of the Prior Art
In cameras having an exposure control circuit such as an electric shutter or the like, a capacitor has been parallel-connected to a power supply battery to reduce the output impedance of the battery. Also, capacitors for preventing oscillation have been used in many of the exposure control circuits. As the result, during the closing of the main switch, the circuit operation is unstable before the charging of these capacitors has been completed. Therefore, for example, in a single lens reflex camera wherein the power source switch of the exposure control circuit is closed in the course of the depression of a shutter release button and shutter release is started at the extremity of the depression, if the release button has been momentarily depressed to its extremity, shutter relase is started before the operation of the exposure control circuit becomes stable and as the result, there is an undesirable possibility that exposure control is not effected accurately.